Medical monitoring devices are used extensively in hospitals, clinics, alternative site care, i.e., nursing homes, and at home to monitor a variety of medical conditions. These devices basically measure a physiologic condition/state/value from a patient and report the data representative thereof as an output of the device, typically by displaying the data on a display of the monitoring device. For example, when a measurement has been completed by a non-invasive blood pressure monitor, the systolic, diastolic, and mean blood pressure as well as the heart rate are displayed on the monitoring device. Such information could also be recorded manually by the patient or a health care provider or possibly stored in the device for future display.
Medical treatment/therapeutic devices are also used extensively in health care. These devices typically deliver a therapeutic treatment to a patient as part of the medical treatment. Examples are infusion pumps (delivering fluids and/or drugs to the patient), and ventilators (delivering gas to the patient). Each therapeutic device has a number of settings that can be modified. This is typically accomplished by various input peripherals such as buttons, knobs, key pads, and the like on the therapeutic device.
With the rapid development of computer technology, such medical devices are now mainly microprocessor-based. This technology now allows for the addition of external communications features (input/output) on the devices. At first, this communication was geared toward technicians to service the device and sometimes use the device to print out tables of data. Over the last 5 years, however, there has been a move to using this communication feature to report the output data measured by a monitor to another location (often a central office) and to remotely modify settings on a therapeutic device by communicating the appropriate input information.
A direct connection between a single device (monitor or therapeutic device) and a central station can be readily constructed. However, a problem arises in coordinating data and transmissions when multiple monitors and/or therapeutic devices are used simultaneously or interchangeably (especially if such devices were not designed to work together or come from different manufacturers). This is because medical monitoring devices and therapeutic devices differ in at least three aspects: 1) their hardware communication protocol, 2) their software communication protocol, and 3) their data (input and/or output).
In a number of industries, this problem is solved by agreeing on a set of standards to enable computers and devices to connect with one another and to exchange information with as little error as possible (i.e., standardized hardware and software communication protocols and data formats). Some of the known protocols include, for example, OSI (Open Systems Interconnection) and SNA (Systems Network Architecture). There are a multitude of standards affecting different aspects of communication, such as file transfer (XMODEM, ZMODEM), handshaking (XON/XOFF), and network transmissions (CSMA/CD).
To date, unfortunately, no standards have been developed that govern the communication process and protocols for medical devices. As a result, the data that is communicated is non-standardized, differs from manufacturer to manufacturer and even sometimes differs with various software versions of the same device. In addition, configuration data needed to start the communication process is also non-standardized.
For example, a certain hardware protocol for serial connections (e.g., RS-232, RS-422/423/449, etc.) may be defined by a number of communication parameters (e.g., baud rate, data bits, stop bits and parity). Each of the parameters have a number of settings (e.g., baud rates of 300, 600, 1200, 2400, 9600, 19200, 38400, 57600, 115200, etc.) which have not been standardized between devices. Devices also have different software communication protocols which define various formatting of data, such as if the data is designed for a line printer versus packetized data. The format is generally the structure or appearance of a unit of data. For line printers, there are parameters defining end of line characters and formats for the line. In packetized data, for example, there are parameters defining formats (packet, data), headers, and end of packet information. Again, each of these parameters include a variety of settings which are not standard in the industry. That is, none of the settings for the above-noted parameters have been standardized. Therefore, for each device, the setting information for each parameter must be determined and configured. This process is tedious and time consuming. It requires a great deal of repetition and additional software and consumes more resources such as RAM, CPU time, coding, and the like. To avoid this problem, many choose to restrict their choice of devices to the same manufacturer where the parameter settings are hopefully the same. However, this does not provide a solution to the problem, since certain manufacturers do not sell all of the devices which may be necessary or do not provide a desired device with certain features.
Consequently, a need arises for providing a way to efficiently connect to these various devices, regardless of manufacturer and/or communication protocol parameter settings.